This invention relates to cooker-warmers using electric heaters and having a cooking function and a warming function.
Where rice is cooked with a rice cooker having an electric heater and the cooked rice is warmed also with an electric heater, use is made of a temperature switch for the purpose of switching a power supply from the side of the cooking heater to the side of the warming heater in accordance with the detection of a cooking end temperature. For detecting temperature a mechanical switch, for instance one making use of changes with temperature in the magnetic permeability of a magnetic shunt alloy, is used. Such a mechanical temperature switch, however, is incapable of accurately setting an operating temperature. Therefore, the cooking end temperature is not fixed but fluctuates, so that it is impossible to always obtain satisfactory results while rice cooking. Also, if this temperature switch is used to provide the rice cooker with a warming function, it is possible that the temperature of the cooked rice is excessively low or excessively high, resulting in such inconvenience as the burning of the cooked rice.